I am a new user in R, and I have a dataset with 5000 variables. I am looking to add 1 for every 100 numerical variables, but I am not sure how I can determine these variables out of the huge dataset or what the formula could be. Just to make it clearer, the variable names that I want to add 1 for each one of them range from B-ARP, so I want to make something like this: B-ARP + 1. Perhaps this is a simple question, but I just started using R yesterday because I was using Stata.
I found this code bellow from another question but I am not sure if it is apply to my situation. library(dplyr) df %>% mutate(across(
Consider this data frame and say, we want to add 999 to columns X4 to X7.
dat
# X1 X2 X3 X4 X5 X6 X7 X8 X9 X10
# 1 0 0 0 0 0 0 0 0 0 0
# 2 0 0 0 0 0 0 0 0 0 0
# 3 0 0 0 0 0 0 0 0 0 0
# 4 0 0 0 0 0 0 0 0 0 0
# 5 0 0 0 0 0 0 0 0 0 0
First, we could identify which columns have those names,
rg <- which(names(dat) %in% c('X4', 'X7'))
rg
# [1] 4 7
and make a numerical sequence out of it.
cols <- seq.int(rg[1], rg[2])
cols
# [1] 4 5 6 7
(Alternatively using do.call:)
cols <- do.call(seq.int, as.list(rg))
## or altogether:
cols <- do.call(seq.int, as.list(which(names(dat) %in% c('X4', 'X7'))))
Then just add 999 to subset dat[cols].
dat[cols] <- dat[cols] + 999
dat
# X1 X2 X3 X4 X5 X6 X7 X8 X9 X10
# 1 0 0 0 999 999 999 999 0 0 0
# 2 0 0 0 999 999 999 999 0 0 0
# 3 0 0 0 999 999 999 999 0 0 0
# 4 0 0 0 999 999 999 999 0 0 0
# 5 0 0 0 999 999 999 999 0 0 0
Data:
dat <- data.frame(matrix(0, 5, 10))